Franklin c



- is used.

' The time of soaking depends on the size of UNITED STATES FRANKLIN O.ROBINSON AND WILLIAIVf IL OOTHREN, OF BRUNSWICK, ME.

PATENT OFFICE.

PROCESS OF TREATING ARTICLES MADE OF EAPER-STOCKOR w000 PULP, no.

SPECIFICATION forming part of Letters Patent No. 347,200, dated August10, 1886.

Application filed May 18, 1886. Serial No. 202,570. (No specimens.)

T0 aZZ whom it may concern.-

Be it known that we, FRANKLIN G. ROBIN- soN and WILLIAM H. COTHREN, bothcitizens of the United States, residing at Brunswick, in the county ofCumberland and State of Maine, have invented certain new and usefulImprovements in the Process of Treating Articles Made of Paper-Stock orWood Pulp, and in the articles so produced, of which the following is aspecification.

It has been found to be a matter of great importance to water-proof andharden hollow and other articles made of paper or wood pulp, so that thesame shall be rendered impervious to moisture, proof against the actionof acids or alkalies, and hard enough to be capable of sustaining apolish.

The necessity for such an invention as above is rendered greater as themanufacture of the articles referredto is increasing very rapidly.Heretofore attempts have been made to gain the designed ends by the useof a mixture of which linseed or other oil was a principal element; butthe use of such a compound does not seem to have fully compassed all theconditions of the case, or to have insured the desired result.

Our invention is designed to accomplish the desired result by a processwherein oil is not used, and whereby a product is obtained peculiarlyperfect for all the uses to which it may properly be put, all as willnow be set forth more fully and in detail.

We melt together paraffine-wax and resin in varying proportions,according to the character of the article we wish to turn out. If wedesire a very stiff,firm precinct, more resin In general we use one partof resin to two of parafline. The article to be, treated, whether it bea pail, flat card-board, or, in fact,anything that can be made ofpaper-stock or wood pulp, is dipped in this hot mixture.

the article and the quality of the product desired. In general thearticle is thoroughly saturated or impregnated with the solution thatis,the paper stock or body is soaked full, but no excess is left on thesurface. This treatment is sufficient for many articles,as the near thatof boiling water its filling may not be softened, so that some of theparaffine and resin will be liable to appear on thesurface, we nextplace the article thus treated in an oven and heat it at a temperatureof about 110 centigrade. Oxidation takes place, and

the heating is continued till the surface of the article becomes dry andhard. The time of heating is dependent on the proportions of the resinand paraffine, the size and uses to which the article is to be put, &c.The articles thus treated have a hard, glossy, orsmooth surface; willout like box-wood; can be worked with tools; are not affected. by acids,alkalies, or boiling water, 850., and are flexible.

If an article is desired to resist great wear on its surface,thearticle, treated as above, is covered with acoat of water-glass, andthen the water-glass is made insoluble in one or two ways. It can bemade insoluble by brushing it over with dilute chlorhydric acid, or,preferably,by heating it'(the article) again. In the latter case thearticle becomes covered with a fine glossy coating,like a pottery-glaze.

Having now described our invention, what we consider new, and desire tosecure by Letters Patent, is

1. The above-described process of treating articles made of paper orwood pulp by a heated mixture composed of one part resin and two partsparaffine and then heating the same, whereby the article is hardened andsolidified and has a smooth surface, substantially as described.

2. The described process of treating articles made of paper or Woodpulp, consisting in soaking or impregnating the same with a hot mixtureof resin and paraffine and producing FRANKLIN O. ROBINSON. WILLIAM H.OOTHREN.

YVitnesses:

ARTHUR F. BELCHER, HERBERT C. WnIrrEMoRE,

